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排序方式: 共有810条查询结果,搜索用时 15 毫秒
1.
Sonoelasticity imaging of prostate cancer: in vitro results 总被引:2,自引:0,他引:2
2.
We interviewed 290 pregnant women randomly selected from public and private prenatal clinics, 80 per cent of whom were at least five months pregnant (ages 18-43, 42 per cent Latino, 22 per cent Black). Twenty-four women reported physical battering during this pregnancy (44 reported physical battering before the current pregnancy). Eight of the 24 pregnant women had sought medical treatment for injuries sustained; none reported having been assessed by prenatal care providers for abuse. 相似文献
3.
Screening for early ovarian cancer 总被引:5,自引:0,他引:5
4.
The vascularity of 49 renal masses (26 malignant and 23 benign lesions) was investigated with duplex Doppler ultrasound. Doppler signals obtained at the margins of renal masses were defined as "tumor signals" when the Doppler-shifted frequency of the lesion exceeded the frequency shift in the ipsilateral main renal artery. These exceeded 2.5 kHz with a 3-MHz insonating frequency. Among the 26 renal masses that subsequently proved to be malignant, tumor signals were obtained in 15 of 18 (83%) untreated renal cell carcinomas, in three of four Wilms tumors, and in two patients with metastases to the kidney, but not in the one patient with lymphoma. None of the 23 benign renal masses demonstrated tumor signals. Tumor vascularity in malignant lesions gives rise to abnormal, high-velocity, Doppler-shifted signals that can help in the differential diagnosis of renal masses. 相似文献
5.
Detection of reactive oxygen species (ROS) and apoptosis in human fragmented embryos 总被引:8,自引:2,他引:8
Yang HW; Hwang KJ; Kwon HC; Kim HS; Choi KW; Oh KS 《Human reproduction (Oxford, England)》1998,13(4):998-1002
In human in-vitro fertilization (IVF)-embryo transfer, the in-vitro culture
environment differs from in-vivo conditions in that the oxygen
concentration is higher, and in such conditions the mouse embryos show a
higher concentration of reactive oxygen species (ROS) in simple culture
media. ROS are believed to cause damage to cell membranes and DNA
fragmentation in somatic cells. This study was conducted to ascertain the
level of H2O2 concentration within embryos and the morphological features
of cell damage induced by H2O2. A total of 62 human oocytes and embryos (31
fragmented, 15 non-fragmented embryos, 16 unfertilized oocytes) was
obtained from the IVF-embryo transfer programme. The relative intensity of
H2O2 concentrations within embryos was measured using
2',7'-dichlorodihydrofluorescein diacetate by Quanti cell 500 fluorescence
imaging and DNA fragmentation was observed with transmission electron
microscopy and an in-situ apoptosis detection kit. The H2O2 concentrations
were significantly higher in fragmented embryos (72.21 +/- 9.62, mean +/-
SEM) compared to non-fragmented embryos (31.30 +/- 3.50, P < 0.05) and
unfertilized oocytes (30.75 +/- 2.67, P < 0.05). Apoptosis was observed
only in fragmented embryos, and was absent in non-fragmented embryos.
Electron microscopic findings confirmed apoptotic bodies and cytoplasmic
condensation in the fragmented blastomeres. We conclude that there is a
direct relationship between increased H2O2 concentration and apoptosis, and
that further studies should be undertaken to confirm these findings.
相似文献
6.
West JA Chichester CH Buckpitt AR Tyler NK Brennan P Helton C Plopper CG 《American journal of respiratory cell and molecular biology》2000,23(1):27-36
Clara-cell populations show a high degree of variation in susceptibility to injury by bioactivated cytotoxicants. Because glutathione (GSH) is critical for detoxification of electrophilic metabolites, heterogeneity in Clara cell GSH levels may lead to a wide range of cytotoxic responses. This study was designed to define the distinct GSH pools within Clara cells, characterize heterogeneity within the population, and examine whether heterogeneity contributes to susceptibility. Using fluorescent imaging combined with high-performance liquid chromatography analysis, semiquantitative measurements were obtained by evaluation of GSH using monochlorobimane and monobromobimane. In steady-state conditions, the GSH measured in isolated cells was in the femtomole range, but varied 4-fold between individual cells. Clara cells analyzed in situ and in vitro confirmed this heterogeneity. The response of these cells to compounds that modulate GSH was also variable. Diethylmaleate depleted GSH, whereas GSH monoethylester augmented it. However, both acted nonuniformly in isolated Clara cells. The depletion of intracellular GSH caused a striking decrease in cell viability upon incubation with naphthalene (NA). The sulfhydryl-binding fluorochrome BODIPY, which colocalized with tetramethylrosamine, a mitochondrial dye, demonstrated by confocal microscopy that cellular sulfhydryls are highest in the mitochondria, next-highest in cytoplasm, and lowest in the nucleus. These pools responded differently to modulators of GSH. We concluded that the steady-state intracellular GSH of Clara cells exists in distinct pools and is highly heterogeneous within the population, and that the heterogeneity of GSH levels corresponds closely to the response of Clara cells to injury by NA. 相似文献
7.
8.
Pathways to care for alcohol use disorders 总被引:1,自引:0,他引:1
9.
Izabela Guimarães Barbosa Natália Pessoa Rocha Aline Silva de Miranda Rodrigo Barreto Huguet Moisés Evandro Bauer Helton José Reis Antônio Lúcio Teixeira 《Revista brasileira de psiquiatria (S?o Paulo, Brazil : 1999)》2013,35(1):67-69
IntroductionBipolar disorder (BD) is a prevalent, chronic and progressive illness. There is a growing body of evidence indicating that brain-derived neurotrophic factor (BDNF) plays an important role in the pathophysiology of BD.ObjectiveThe aim of this study was to evaluate BDNF plasma levels in BD patients with long term illness in comparison with controls.Methods87 BD type I patients and 58 controls matched by age, gender and education level were enrolled in this study. All subjects were assessed by the Mini-International Neuropsychiatric Interview and the patients by the Young Mania Rating Scale and the Hamilton Depression Rating Scale. The plasma levels of BDNF were measured by ELISA.ResultsOn average, patients had suffered from BD for 23.4 years. In comparison with controls, BD patients with mania presented a 1.90-fold increase in BDNF plasma levels (p = .001), while BD patients in remission presented a 1.64-fold increase in BDNF plasma levels (p = .03). BDNF plasma levels were not influenced by age, length of illness or current medications.ConclusionsThe present study suggests that long-term BD patients exhibit increased circulating levels of BDNF. 相似文献
10.